The method and the device disclosed herein serve to package perishable food such as meat products. The problem occurring with some prior methods and devices is that liquid may leak out during the time of storage and ripening, deteriorating the storage life by an enhanced growth of germs in the liquid.
In practice, in a simple case, meat pieces are placed in an appropriate film bag and evacuated and sealed in a vacuum chamber machine. Since the bags are always bigger than the products, excessive film remains and creases can develop. When using a shrinkable film, the wrapping is shrunk by a subsequent heat wrapping on the package and a skin-tight fitting of the film is attained. A disadvantage of this method of packaging is the high personnel costs. A further kind of packaging is the so-called vacuum deep-drawing packaging, as it is known from DE-A-2 364 565. Here, trays in which the product to be packaged is placed are formed from a lower film layer. The so-filled container is brought into a vacuum chamber together with a covering upper film layer and is evacuated and sealed there. In the chamber, the tray formed of the lower film is subjected to heat, whereby shrinking forces are released leading to the lower film nestling to the good to be packaged. A package formed in this way is shown in FIG. 6. It has the disadvantage that the lower film and the upper film are in contact with each other without being sealed together in a region between the product and the sealing rim, and that creases exist in the region in which the lower film and the upper film are in contact. In the course of the time of ripening, meat liquid enters into this non-sealed section between the lower film and the upper film.
From EP-A-127 016, a method is known in which the heating for the purpose of shrinking of the deep-draw package is effected by vapor. Here, the same disadvantages are present as in the package described above.
It is an object of the invention to provide a method and a device as well as a package enabling a long storage life of food such as meat, wherein, for marketing, the package shall have an appealing appearance.
This object is solved by the method described in claim 1, the device described in claim 6 and the package described in claim 9.